Modular interconnect matrix for matrix connection of a plurality of antennas with a plurality of radio channel units

ABSTRACT

A modular interconnect matrix (200) interconnects a plurality (M) of radio channel units (203) with a plurality (N) of antennas (202). Each radio channel unit (203) is connected to a first connector (222) on a corresponding first switching module (217) having a plurality (N) of seconds connectors (225). Each antenna (202) is connected to a first connector (212) of a corresponding antenna interface module (205) having a plurality (X) of second connectors (215). The second connectors (215,225) on the modules (205,217) are arranged for interconnection of at least one second connector (225) on each of the first switching modules (217) with at least one second connector (215) on each of the antenna interface modules (205). Each of the first switching modules (217) provides for the connection of the first switching module first connector (222) with any one of its second connectors (225) under control of a switch control portion of the matrix (240, 260, 263, 267), thereby allowing each radio channel unit (203) to be interconnected to any one of the antennas (202).

TECHNICAL FIELD

The present invention relates to the interconnection of radios withantennas, and more particularly, to a modular interconnect matrix forthe matrix connection of any one of a plurality of radios with any oneof a plurality of antennas.

BACKGROUND OF THE INVENTION

In a land mobile radio base site, a number of antennas are typicallyused to transmit and receive RF signals for a plurality of radio channelunits (radios). In such known systems, each radio channel unit comprisesa transmitter section for the generation and transmission of RF signalsat the operating frequency of the radio channel unit and a receiversection for receiving RF signals at the operating frequency of the radiochannel unit.

For the transmission of RF signal, each antenna is connected to one ormore of the radio channel units for transmitting signals provided by thetransmitter section of the corresponding radio channel units. If morethan one radio channel unit is designated to transmit RF signals via asingle antenna, the RF signals provided by the radio channel units arecombined in a combiner, and the combined RF signals are provided by thecombiner to the antenna for transmission thereof.

For the receipt of RF signals, each antenna is connected to one or moreof the radio channel units for providing received RF signals to thereceiver section of the radio channel units. If the antenna isdesignated to provide received RF signals to more than one radio channelunit, the output of the antenna is connected to a splitter which splitsthe received RF signal from the associated antenna into a plurality ofequal power parts. The parts of the received RF signal are then providedto the associated radio channel units. If the radio channel unitcomprises a diversity receiver, e.g., a receiver having two inputs andcapable of selecting the strongest RF signal between the two RF signalsfor demodulation, then the radio channel unit is connected to twoantennas.

In the above described land mobile radio base site, each radio channelunits is directly connected to one or two dedicated antennas for thetransmission and receipt of RF signals. Therefore, the antennas usedmust have generally omni-directional characteristics to ensure theproper receipt of RF signals from, and the transmission of RF signalsto, mobile radios (mobile subscribers).

It is generally known that improved transmission and receipt of RFsignals between a radio channel unit at a mobile radio base site and amobile subscriber may be achieved using an array of directional antennasat the mobile radio base site. However, in such a mobile radio base sitehaving a large number of radio channel units, e.g., 60 radio channelunits, and a large number of directional antennas, e.g., 16 directionalantennas, a significant problem exists with respect to interconnectingthe transmitter section and receiver section of the radio channel unitsto the directional antennas for optimal transmission and receipt of RFsignals, respectively.

SUMMARY OF THE INVENTION

Objects of the invention include a modular interconnect matrix formatrix connection of any one of a plurality of radio channel units withany one of a plurality of antennas.

Another object of the present invention is to provide a modularinterconnect matrix having a plurality of modules which may be quicklyassembled for matrix connection of a plurality (N) of antennas with aplurality (M) of radio channel units.

A further object of the present invention is to provide a modularinterconnect matrix with modules having coaxial quick-disconnectconnectors for matrix connection of a plurality (N) of antennas with aplurality (M) of radio channel units.

Another object of the present invention is to provide a modularinterconnect matrix having a plurality of modules which are easy andeconomical to manufacture, and which provide for easy assembly for thematrix connection of a plurality (M) of radio channel units with aplurality (N) of antennas.

A still further object of the present invention is to provide a modularinterconnect matrix for dynamically connecting a receive terminal ofeach one of a plurality of radio channel units with any one of aplurality of antennas which, on average during a sampling period, hasthe strongest received signal strength of RF signals at the operatingfrequency of the one radio channel unit.

Another object of the present invention is to provide a modularinterconnect matrix for dynamically interconnecting a transmit terminalof each one of a plurality of radio channel units with any one of aplurality of antennas which, on average during a sampling period, isbest suited for transmitting RF signals at the operating frequency ofthe one radio channel unit in a direction corresponding to the desireddestination for the transmitted RF signals.

According to the present invention, a modular interconnect matrixinterconnects a plurality (M) of radio channel units with a plurality(N) of antennas; each radio channel unit is connected to a firstconnector on a corresponding first switching module having a plurality(N) of seconds connectors, and each antenna is connected to a firstconnector of a corresponding antenna interface module having a plurality(X) of second connectors; the second connectors on the first switchingmodules are configured for interconnection with the second connectors onthe antenna interface modules and the second connectors on the modulesare arranged for interconnection of at least one second connector oneach of the first switching modules with at least one second connectoron each of the antenna interface modules; each of the first switchingmodules provides for the connection of the first connector with any oneof the second connectors, thereby allowing each radio channel unit to beinterconnected to any one of the antennas.

In further accord with the present invention, a switch control isprovided which controls the interconnection of the first connector toany one of the second connectors on the first switching modules.

According further to the present invention, a pair of modularinterconnect matrices are provided including a radio signal transmitmodular interconnect matrix for interconnecting a transmit terminal ofeach one of the radio channel units with any one of the antennas for thetransmission of RF signals, and a radio signal receive modularinterconnect matrix for interconnecting a receive terminal of each oneof the radio channel units with any one of the antennas for providing RFsignals received by the antennas to the corresponding radio channelunits.

According still further to the present invention, in the radio signalreceive modular interconnect matrix, the first connector on each firstswitching module is connected to a receive connector on thecorresponding radio channel unit, and each antenna interface module is asplitter which divides a signal received from the corresponding antennainto a plurality (X) of divided signals each having an equal signalstrength which is a fraction (1/X) of the received signal strength.

In still further accord with the present invention, the switch controlcomprises a plurality (Y) of second switching modules having a plurality(N) of second connectors and a first connector connected to a scanningreceiver, each scanning receiver being associated with correspondingones of the radio channel units; the second connectors on the secondswitching modules are configured for interconnection with the secondconnectors on the antenna interface modules and the second connectors onthe modules are arranged for interconnection of at least one secondconnector on each second switching module with at least one secondconnector on each of the antenna interface modules. Each secondswitching module is configured for interconnecting each scanningreceiver with any one of the antennas, and each scanning receiverprovides output data signals to a micro-controller indicative of thereceived signal strength on each of the antennas at the operatingfrequencies of the corresponding ones of the radio channel units fordetermining the antenna having the strongest signal strength at theassigned frequency of the corresponding ones of the radio channel units,the micro-controller further providing control signals to the firstswitching modules for interconnecting each radio channel unit with theantenna indicated as having the strongest signal strength at theoperating frequency of the radio channel unit.

According further to the present invention, in the radio signal transmitmodular interconnect matrix, the first connector on each first switchingmodule is connected to a transmit connector on the corresponding radiochannel unit, and each antenna interface module is a combiner whichcombines RF signals provided on its second connectors from the radiochannel units into a combined RF signal which is provided to acorresponding antenna via the antenna interface module second connector.

According further to the present invention, each radio channel unit hasa diversity receiver capable of receiving signals from two antennas anddetermining the signal having the strongest signal strength, and eachfirst switching module in a radio signal receive modular interconnectmatrix is provided with two first connectors for interconnection withthe two diversity receiver connectors of the corresponding radio channelunit diversity receiver, the micro-controller provides control signalsto the first switching modules indicative of the two antennas having thestronger signal strength at the operating frequency for each of theassociated radio channel units, and the first switching modulesinterconnect one of the first connectors with the antenna having thestrongest signal strength and the other of the first connectors with theantenna having the second strongest signal strength.

In still further accord with the present invention, the micro-controllercontrols each first switching module in the radio signal transmitmodular interconnect matrix such that the first connector isinterconnected with the antenna indicated as having the strongest signalstrength when a signal is received for the corresponding radio channelunit in the radio signal receive modular interconnect matrix.

The present invention provides a significant improvement over the priorart by providing a modular interconnect matrix between a plurality ofradio channel units and a plurality of antennas. Such a modularinterconnect matrix allows for the use of a plurality of directionalantenna at a land mobile radio base site for improved transmission andreceipt of RF signals. Additionally, the modular components which makeup the matrix may be easily manufactured and tested, and thereforeprovide a simple and economical means of interconnecting radio channelunits with antennas. The modular units of the modular interconnectmatrix are easy to assemble, and provide a reliable connection betweenany one radio channel unit with any one antenna.

The foregoing and other objects, features and advantages of the presentinvention will become more apparent in light of the following detaileddescription of exemplary embodiments thereof, in view of theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows the relation between FIGS. 1A and 1B;

FIGS. 1A and 1B together are a schematic block diagram of the modularinterconnect matrix of the present invention;

FIG. 2 is a perspective view of a splitter/combiner module of themodular interconnect matrix of FIG. 1;

FIG. 3 is a perspective view of a first switching module of the modularinterconnect matrix of FIGS. 1A and 1B;

FIG. 4 is a perspective view of a second switching module of the modularinterconnect matrix of FIGS. 1A and 1B;

FIG. 5 is a perspective view of the modular interconnect matrix of FIGS.1A and 1B;

FIG. 6 is a side view of a coaxial quick-disconnect connector;

FIG. 7 is a side view of a coaxial quick-disconnect connector;

FIG. 8 is a schematic block diagram of a modular interconnect matrixused for transmitting RF signals;

FIG. 9 is a schematic block diagram of a first alternative embodiment ofthe modular interconnect matrix of FIGS. 1A and 1B; and

FIG. 10 is a schematic block diagram of a second alternative embodimentof the modular interconnect matrix of FIGS. 1A and 1B.

BEST MODE FOR CARRYING OUT THE INVENTION

Referring to FIGS. 1A and 1B, the modular interconnect matrix 200 isused to interconnect a plurality (N) of antennas 202 to a plurality (M)of a radio channel units 203. FIGS. 1A and 1B is an example of a radiosignal receive modular interconnect matrix, e.g., a modular interconnectmatrix which is used to provide signals received on antennas 202 toreceive terminals mounted on the radio channel units 203. Although theinvention is described and illustrated in FIGS. 1A and 1B with respectto the receipt of signals by the radio channel units, the invention isequally applicable to the transmission of RF signals provided by theradio channel units, as will be described in greater detail hereinafter.

The modular interconnect matrix 200 comprises a plurality (N) of signalsplitter modules 205, one signal splitter module 205 being associatedwith each of the antennas 202. Each antenna 202 is connected to itsassociated signal splitter modules 205 via a band pass filter 208 and anadjustable preamplifier 210 which amplifies the received signals beforebeing provided to the signal splitters 205. In FIGS. 1A and 1B, sixteen(16) antennas 202 are shown interconnected to sixteen (16) signalsplitter modules 205. The signal splitter modules 205 are power dividerswhich divide the amplified RF signals into a plurality (X) of equalparts, e.g., each of the equal parts has an identical signalcharacteristic (shape) as the amplified RF signal at a fraction (1/X) ofthe signal strength. For example, a 20-way power divider having afrequency range of 824 to 894 MHZ and an insertion loss of 16 dB may beselected for use as a signal splitter. In FIG. 2, each signal splittermodule 205 is illustrated as dividing the received RF signal into 20equal parts.

Referring also to FIG. 2, the signal splitter module 205 comprises aninput connector 212 where the amplified signals provided by the antennaare input to the signal splitter module 205. The signal splitter module205 also comprises a plurality (X) of output connectors 215 where theequal parts of the amplified RF signals are provided. FIG. 3 illustratesthe signal splitter module 205 having 20 output connectors.

Referring again to FIG. 1A and 1B, the modular interconnect matrix 200also comprises a plurality (M) of first switching modules (radioswitching modules) 217. There is one first switching module 217associated with each radio channel unit 203. Referring also to FIG. 3,each of the first switching modules 217 comprises a pair of firstconnectors 222 for interconnection with a pair of receiver connectors onthe corresponding radio channel unit 203 (FIG. 1A and 1B). Each firstswitching module 217 also comprises a plurality (N) of second connectors225. Each of the first connectors 222 and second connectors 225 areconnected to an electronic switch 230 located within the first switchingmodule 217. The electronic switch 230 is also connected to a groundconnector 231, a power supply connector 232 and a control connector 235mounted on the first switching module 217. As will be described ingreater detail hereinafter, the electronic switch 230 is a2-pole-N-throw switch which operates under control of control signalsprovided to the control connector 235 for connecting each one of thefirst connectors 222 to one of the second connectors 225. The electronicswitch 230 may be a two-pole-sixteen-throw electronic switch SW9481manufactured by the Celwave Division of Radio Frequency Systems, Inc.,which is powered by a 15 VDC power supply and is controlled by a pulsewidth modulated data stream containing both timing (clock) data andcontrol (switching) data.

Referring now to FIGS. 1, 2, 3 and 5, the second connectors 215, 225 onboth the signal splitter modules 205 and the first switching modules 217are configured and arranged such that each one of the second connectors225 on the first switching modules 217 may be interconnected to onesecond connector 215 on each signal splitter module 205. It willtherefore be understood by those skilled in the art that using the abovedescribed arrangement, each one of the first switching modules 217 isprovided with a portion (1/X) of the RF signal output of each antenna202 due to the matrix interconnection of the first switching modules 217with the signal splitter modules 205.

Referring to FIG. 2, to achieve the above described matrixinterconnection of the first switching modules 217 with the signalsplitter module 205, the signal splitter module 205 comprises a housing236 which is generally rectangular in shape with the first connector 212mounted at the center of one of the shorter (minor axis) sides of therectangle. The second connectors 215 of the signal splitter module 205are divided into two groups and are equally spaced on opposite long(major axis) sides of the rectangular shaped housing. Both the firstconnector 212 and the second connectors 215 on the signal splittermodule 205 are male coaxial quick disconnect connectors 238 of the typeillustrated in FIG. 6.

Referring to FIG. 3, the first switching module 217 also comprises agenerally rectangular shaped housing 237. The first connectors 222 areevenly spaced about a central point of one long (major axis) side of thefirst switching module housing 237. The second connectors 225 arepositioned on the other long (major axis) side of the housing 237 withthe ground connector 231, the power connector 232 and the controlconnector 235. All of the connectors on the first switching module 217are female coaxial quick disconnect connectors 239 of the typeillustrated in FIG. 7.

The male and female coaxial quick disconnect connectors 238, 239illustrated in FIGS. 6 and 7 may be selected from known connectors whichare designed for interconnection with one another for providing aconnection therebetween. The dimensions of the connectors are selectedsuch that when the male and female connectors are interconnected, thereis sufficient friction therebetween to provide a strong and secureconnection without the requirement of threads or other interlockingmeans.

Referring now to FIGS. 2, 3 and 5, the arrangement of the secondconnectors 225 on the first switching module 217 is selected such thatwhen the signal splitter modules 205 are arranged adjacent to oneanother with the rows of second connectors 215 parallel to one another,the second connectors 225 of a first switching module 217 placedperpendicular to the parallel rows of second connectors 215 of thesignal splitter module 205 will engage with one another.

Referring again to FIGS. 1A and 1B, a plurality (Y) of second switchingmodules 240 are also provided for interconnection with the signalsplitter modules 205. Referring also to FIG. 4, the second switchingmodule 240 comprises a generally rectangular shaped housing 242. Mountedon one of the long (major axis) sides of the housing 242 is a firstconnector 245, and mounted on the other long (major axis) side of thehousing is a plurality (N) of second connectors 248, a ground connector250, a power connector 251 and a control connector 254. Located withinthe second switching module housing 242 is an electronic switch 257which is interconnected to all of the connectors 245, 248, 250, 251, 254mounted on the second switching module 240. The electronic switch 257 isa one-pole-N-throw switch which interconnects the first connector 245 toany one of the second connectors 248 under control of control signalsprovided via the control connector 254, as will be described in greaterdetail hereinafter. The electronic switch 257 may be aone-pole-sixteen-throw electronic switch SW9480 manufactured by theCelwave Division of Radio Frequency Systems, Inc., which is powered by a15VDC power supply and is controlled by a pulse width modulated datastream containing both timing (clock) data and control (switching) data.

Referring again to FIGS. 1A and 1B, the first connector 245 (FIG. 4) oneach of the second switching modules 140 is connected to a correspondingRF scanning receiver 260. Associated with each RF scanning receiver 260is a phase locked loop (PLL) device 263 and a micro-controller 267,e.g., a HC11F1 (PLL) manufactured by Motorola. As will be described ingreater detail hereinafter, the micro-controller 267 controls the phaselocked loop 263, which in turn controls the receiving frequency of theRF scanning receiver so as to sequentially receive RF signals atselected frequencies associated with certain ones of the radio channelunits 203, and the micro-controller 267 also controls the secondswitching module 240 to sequentially interconnect the RF scanningreceiver 260 with the antennas 202 via the splitters 205. The RFscanning receiver 260 then determines which antennas 202 have thestrongest signal strength at the operating frequencies of the selectedradio channel units 203, and provides an indication thereof to themicro-controller 267. The micro-controller 267 then controls the firstswitching modules 217 of the selected radio channel units 203 tointerconnect with the two antennas 202 having the strongest signalstrength.

Referring again to FIGS. 2, 4 and 5, as with the first switching modules217, all of the second connectors 248 on the second switching modules240 are female coaxial quick disconnect connectors 239 of the typeillustrated in FIG. 7. Additionally, as with the first switching modules217, the second connectors 248 on the second switching module 240 arearranged such that when placed perpendicular to the rows of secondconnectors 215 on the signal splitter module 205, the second connectors248, 215 interconnect with one another.

The operation of the radio signal receive modular interconnect matrix200 is best understood by example. Referring to FIGS. 1A and 1B, fifteen(15) first switching modules 217 are provided for connection to fifteen(15) corresponding radio channel units 203. The radio channel units 203and first switching modules 217 are divided into groups of equalnumbers, and each group is associated with a corresponding secondswitching module 240, RF scanning receiver 260, micro-controller 267 andphrase locked loop 263. In the example of FIGS. 1A and 1B, the firstswitching modules 217 and radio channel units 203 are divided into fivegroups of three. Therefore, there are five second switching modules 240,RF scanning receivers 260, phase locked loops 263 and micro-controllers267.

There are 16 signal splitter modules 205, one being associated with eachantenna 202. Each of the signal splitter modules 205 comprises twentysecond connectors 215. On each of the signal splitter modules 205,fifteen of the second connectors are provided for interconnection withthe fifteen first switching modules 217, and the remaining five secondconnectors 215 on the signal splitter module 205 are provided forinterconnection with the five second switching modules 240. Theinterconnection of the signal splitter modules 205, first switchingmodules 217 and second switching modules 240 is illustrated in FIG. 5.The signal splitter modules 205 are arranged adjacent to each other withthe two rows of second connectors 215 on each signal splitter module 205arranged parallel to the rows of second connectors 215 on the othersignal splitter modules 205. Ten of the first switching modules 217 arearranged adjacent to one another with their rows of second connectors225 parallel to one another and perpendicular to the rows of secondconnectors 215 on the signal splitter modules 205. The male and femalecoaxial quick disconnect connectors 238, 239 (FIGS. 6 and 7) are theninterconnected with one another such that at least one of the secondconnectors 225 on each of the ten first switching modules 217 isinterconnected with at least one of the second connectors 215 on each ofthe sixteen signal splitter modules 205. The remaining five firstswitching modules 217 and the five second switching modules 240 arearranged in a like manner on an opposite side of the sixteen adjacentsignal splitter modules 205.

Using the above described modular interconnect matrix, variousrelationships are established based on the following parameters:

N=the number of antennas.

M=the number of radio channel units.

Y=the number of groups the radio channel units are arranged in.

The relationships established by the above recited parameters include:

The number of signal splitter modules=N

The number of first switching modules=M

The number of second switching modules=Y

The number of second connectors on the first and second switchingmodules=N

The number of second connectors on the signal splitter modules=X=(M+Y)

Each micro-controller 267 controls a corresponding phase locked loop263, second switching module 240 and three first switching modules 217in each one of the five groups. Each radio channel unit 203 transmitsand receives RF signals on an assigned (operating) frequency, and thephase locked loop 263 is configured to control the receiving frequencyof the RF scanning receiver for sequentially receiving RF signals atthree different frequencies, each of the three frequencies correspondingto the operating frequencies of the three radio channel units in itscorresponding group. Under control of the micro-controller 267, thesecond switching module 240 selects one of the sixteen antennas 202. Thesignals provided by the antenna 202 are provided via the band passfilter 208 to the adjustable amplifier 210 where the received signalsare amplified. Next the received signal is provided to the correspondingsignal splitter module 205 where the signal is divided into 20 equalparts. One of the equal parts is provided to each of the secondswitching modules 240.

A control signal is provided on a line 270 from the micro-controller 267to the control terminal 254 (FIG. 4) of the second switching module 240for controlling the position of the one-pole-sixteen-throw switch 257(FIG. 4) of the second switching module 240 for antenna selection. Thepart of the amplified RF signal from the selected antenna is providedvia the first connector 245 (FIG. 4) of the second switching module 240to a line 272 which is connected to the RF scanning receiver 260. Themicro-controller also provides control signals on a line 275 to thephase locked loop 263 once an antenna has been selected to control thephase locked loop to in turn control the receiving frequency of RFscanning receiver 260 so as to sequentially receive RF signals at thethree different frequencies corresponding to the three radio channelunits within the corresponding group. Control signals are provided bythe phase locked loop to the RF scanning receiver 260 on a line 278.First, the RF scanning receiver 260 measures the power level of the RFsignal on the line 272 at the first frequency under control of the phaselocked loop. The RF scanning receiver provides a signal on a line 280 tothe micro-controller 267 indicative of the power level of the signal onthe line 272 at the first frequency. The micro-controller 267 thenprovides a control signal on the line 275 to the phase locked loop 263,which in turn controls the RF scanning receiver 260 to receive RFsignals at the second frequency. The RF scanning receiver then providesa second measurement of the power level of the received signal at thesecond excitation frequency on the line 280 to the micro-controller 267.This procedure is repeated for the third frequency.

After measurements are taken on one antenna at the three differentexcitation frequencies, the micro-controller provides a control signalon the line 270 to the second switching module 240 for selection of thenext antenna 202. The signal provided by the next antenna 202 is thenmeasured at the three excitation frequencies and these measurements arerecorded by the micro-controller 267. This procedure is repeated for allsixteen antennas 202. Each antenna 202 is sampled at all threefrequencies approximately 8 times per second. The micro-controller 267maintains a running average of the received signal strength at the threeradio channel unit operating frequencies for all sixteen antennas, andprovides a control signal on a line 285 to each of the first switchingmodules 217 in the corresponding group indicative of the two antennashaving the strongest signal strength at the operating frequency of thecorresponding radio channel unit. The electronic two-pole-16-throwswitch 230 (FIG. 3) in the first switching module 217 connects two ofthe second connectors 225 (FIG. 3) to the two first connectors 222 (FIG.3) in response to the control signal on the line 285 from themicro-controller 267. As is known in the art, the radio channel unitdiversity amplifier then selects between the two input signals forproviding an input to the receiver.

Since the antennas 202 are directional antennas, the micro-controllercontrols the second switching module 240 to sample the antennas 202 sothat adjacent antennas are not consecutively sampled, but rather,antennas from different direction quadrants are sampled consecutively.For example, if the antennas are sequentially numbered 1-16, theantennas may be sampled in the following order: 1, 4, 7, 10, 13, 16, 3,6, 9, 12, 15, 2, 5, 8, 11, 14.

The invention has been described thus far with respect to a radio signalreceive modular interconnect matrix. However, the invention is alsoapplicable to a radio signal transmit modular interconnect matrix, e.g.,a modular interconnect matrix used to interconnect a plurality of radiochannel units with a plurality of antennas for the transmission ofsignals provided by the radio channel units via the antennas.

Referring to FIG. 8, a transmit modular interconnect matrix 900 issimilar to the receive modular interconnect matrix 200 (FIGS. 1A and 1B)except that the first switching module 917 is provided with one firstconnector for interconnection to a transmit terminal of a radio channelunit 203. Additionally, the signal splitter modules 205 (FIGS. 1A and1B) are replaced with combiner modules 905 which combine RF signalsprovided to its plurality of second connectors into a combined RF signalwhich is provided from the first connector via an amplifier 910 andfilter 908 to an antenna 202 for transmission. It is assumed that theantenna 202 indicated as having the strongest received signal strengthat the operating frequency of the radio channel unit is the best antennafor transmission of signals provided by the radio channel unit, andtherefore, a second switching module and corresponding scanning receiverphase locked loop and micro-controller are not required in the transmitmatrix interconnect module 900. Instead, each first switching module ofthe transmit matrix interconnect module is controlled to interconnectits first connector with its second connector corresponding with theantenna having the strongest signal strength at the operating frequencyof the corresponding radio channel unit. Additionally, since the fivesecond switching modules are not required in the transmit modularinterconnect matrix 900, the combiner modules 905 may be configured forconnection with five dummy loads 915 mounted to the five secondconnectors which are not used. Alternatively, each combiner module 905may be provided with only 15 second connectors for interconnection withthe 15 first switching modules.

The invention has been described thus far for interconnecting 15 radiochannel units with the 16 antennas. If it is desired to increase thenumber of radio channel units or the number of antennas, the modularcomponents may be modified accordingly. Alternatively, a plurality ofmodular interconnect matrices may be provided to increase the number ofradio channel units. For example, referring to FIG. 9, four modularinterconnect matrices 930 may be provided, each for interconnection to15 radio channel units and sixteen antennas 202. Each of the modularinterconnect matrices 930 may be connected to the antennas 202 via asecond combiner or splitter 935 for achieving the desired total numberof radio channel units and antennas. As shown in FIG. 10, there are fourmodular interconnect matrices 930 each having 15 radio channel units fora total of 60 radio channel units interconnected to 16 antennas.

The invention has been described herein as using modules which directlyinterconnect with one another for providing the matrix connection of anyone of a plurality of antennas with any one of a plurality of radiochannel units. However, in another embodiment of the invention, ratherthan providing interconnecting modules for creating the matrix, thecomponents of the matrix connection may be interconnected with knowncoaxial cables. An example of such a matrix connection (transmit matrix)using coaxial cables is schematically illustrated in FIG. 10. In a RFsignal transmit interconnection having 60 switches associated with 60radio channel units with 16 antennas via 16 combiners, 960 coaxialcables are required between the combiners and the switches. Similarly,960 coaxial cables are required between 60 switches and 16 splitters forRF signals received by the 16 antennas. Although this embodimentsprovides the desired matrix connection of the radio channel units andthe antennas, the physical mass of cabling and the cost of connectors,cable, and cable assembly and inspection is significant.

Although the invention has been described herein with respect toexemplary embodiments thereof, it will be understood by those skilled inthe art that the foregoing and various other changes, omissions andadditions may be made therein and thereto without department from thespirit and scope of the present invention.

What is claimed is:
 1. A modular interconnect matrix for matrixconnection of a first plurality of antennas with a second plurality ofradio channel units, wherein the antennas and the radio channel unitstransmit and receive RF signals at assigned operating frequencies,comprising:a third plurality of first switching modules, each having atleast one first switching connector and a plurality of second switchingconnectors, each first switching module being connected by its firstswitching connector to a corresponding radio channel unit; firstswitching means in each one of said first switching modules forconnecting each one of said first switching connectors with any one ofsaid second switching connectors; a fourth plurality of antennainterface modules, each having a first interface connector and aplurality of second interface connectors, each antenna interface modulebeing connected by its first interface connector to a correspondingantenna; wherein said second switching connectors are dimensioned forinterconnection with said second interface connectors; wherein saidsecond switching connectors and said second interface connectors arearranged on the respective first switching modules and antenna interfacemodules for interconnection of at least one of said second switchingconnectors on each of said first switching modules with at least one ofsaid second interface connectors on each of said antenna interfacemodules; wherein each radio channel unit is assigned to one group of aplurality of groups; a plurality of second switching modules each havinga first control connector and a plurality of second control connectors,said second control connectors being dimensioned for interconnectionwith said interface connectors, and said second control connectors andsaid second interface connectors being arranged on said second switchingmodules and said antenna interface modules for interconnection of atleast one of said second control connectors on said second switchingmodules, with at least one of said second interface connectors on eachof said antenna interface modules, a respective one of said secondswitching modules being assigned to a respective one of said groups;second switching means in each of said second switching modules forconnecting each first control connector with any one of said secondcontrol connectors; and a plurality of switch control means, eachassigned to a respective one of said groups, for controlling said firstand second switching means, each said switch control means including:arespective frequency control means for sequentially providing frequencycontrol signals each indicative of the operating frequencies of theradio channel units in said respective one of said groups; a respectivescanning receiver means connected to said first control connector ofsaid respective one of said second switching modules, said scanningreceiver means being responsive to said frequency control signals and toRF signals received by the antennas for providing signal strengthsignals indicative of the signal strength of said RF signals at theoperating frequencies of the radio channel units in said respective oneof said groups; and a respective controller responsive to said signalstrength signals for determining the antenna having the strongest signalstrength of the received RF signals at the operating frequency of eachradio channel unit in said respective one of said group.
 2. A modularinterconnect matrix according to claim 1, wherein each of said firstswitching connectors on said first switching modules are connected to areceive terminal on said corresponding one of the radio channel units.3. A modular interconnect matrix according to claim 2, wherein saidantenna interface modules are signal splitter modules each of whichdivides an RF signal received at its first interface connector from saidcorresponding antenna into a plurality of divided RF signals each havingan equal signal strength which is a fraction of the signal strength ofsaid RF signal, said divided RF signals being provided to said secondinterface connectors.
 4. A modular interconnect matrix according toclaim 3, wherein each said respective controller provides controlsignals to respective first switching means of respective firstswitching modules which are connected to radio channel units in saidrespective one of said groups for interconnecting said first switchingconnector with one of said second switching connectors on each of saidrespective first switching modules such that said receive terminal onradio channel units in said respective one of said groups isinterconnected with the antenna having the strongest signal strength ofthe received RF signals at the operating frequency of said radio channelunits.
 5. A modular interconnect matrix according to claim 1, whereineach of said first switching connectors on said first switching modulesare connected to a transmit terminal on said corresponding one of theradio channel units.
 6. A modular interconnect matrix according to claim5, wherein said antenna interface modules are signal combiner moduleseach of which combines RF signals received at its second interfaceconnectors from said transmit terminals into a combined RF signal whichis provided to said first interface connector for transmission by saidcorresponding antenna.
 7. A module interconnect matrix according toclaim 6 wherein each said respective controller provides control signalsto respective first switching means of respective first switchingmodules which are connected to radio channel units in said respectiveone of said groups for interconnecting said first switching connectorwith one of said second switching connectors on each of said respectivefirst switching modules such that said transmit terminal on radiochannel units in said respective one of said groups is interconnectedwith the antenna having the strongest signal strength of the received RFsignals at the operating frequency of said radio channel units.
 8. Amodular interconnect matrix according to claim 1, wherein the radiochannel units each comprise a diversity receiver having two receiveterminals for receiving RF signals, and wherein each of said firstswitching modules has two first switching connectors which are connectedto a corresponding one of said receive terminals on said correspondingone of the radio channel units.
 9. A modular interconnect matrixaccording to claim 8, wherein said antenna interface modules are signalsplitter modules each of which divides an RF signal received at itsfirst interface connector from said corresponding antenna into aplurality of divided RF signals each having an equal signal strengthwhich is a fraction of the signal strength of said RF signal, saiddivided RF signals being provided to said second interface connectors.10. A modular interconnect matrix according to claim 9, wherein eachsaid respective controller provides control signals to respective firstswitching means of respective first switching modules which areconnected to radio channel units in said respective one of said groupsfor interconnecting said first switching connectors with two of saidsecond switching connectors on each of said respective first switchingmodules such that one of said receive terminals on radio channel unitsin said respective one of said groups is interconnected with the antennahaving the strongest signal strength of the received RF signals at theoperating frequency of said radio channel units and another of saidreceive terminals of said radio channel units in said respective one ofsaid groups is interconnected with the antenna having the secondstrongest signal strength of the received RF signals at the operatingfrequency of said radio channel units.
 11. A modular interconnect matrixaccording to claim 1, wherein said respective controller provides secondcontrol signals to said second switching means of said respective secondswitching module for interconnecting said first control connector toeach one of said second control connectors of said respective secondswitching module in a predetermined sequence.
 12. A modular interconnectmatrix according to claim 11, wherein between each second control signalin said predetermined sequence, said respective controller controls saidrespective frequency control means to sequentially provide saidfrequency control signals to said respective scanning receiver means,said frequency control signals corresponding to the operating frequencyof each radio channel unit in said respective one of said groups.
 13. Amodular interconnect matrix according to claim 12, wherein each of saidfirst switching connectors on said first switching modules are connectedto a receive terminal on said corresponding one of the radio channelunits, and wherein said antenna interface modules are signal splittermodules each of which divides an RF signal received at its firstinterface connector from said corresponding antenna into a plurality ofdivided RF signals each having an equal signal strength which is afraction of the signal strength of said RF signal, said divided RFsignals being provided to said second interface connectors.
 14. Amodular interconnect matrix according to claim 12, wherein each of saidfirst switching connectors on said first switching modules are connectedto a transmit terminal on said corresponding one of the radio channelunit, and wherein each antenna interface module includes a signalcombiner module which combines RF signals received at its secondinterface connectors from said transmit terminals into a combined RFsignal which is provided to said first interface connector fortransmission by said corresponding antenna and also include a signalsplitter module which divides an RF signal received at its firstinterface connector from said corresponding antenna into a plurality ofdivided RF signals each having an equal signal strength which is afraction of the signal strength of said RF signal, said divided RFsignals being provided to said second interface connectors, said secondinterface connectors on said signal splitter modules being connected tosaid second control connectors.
 15. A modular interconnect matrixaccording to claim 12 wherein the radio channel units each comprise adiversity receiver having two receive terminals for receiving RFsignals, wherein each of said first switching modules has two firstswitching connectors which are connected to a corresponding one of saidreceive terminals on said corresponding one of the radio channel units,wherein said antenna interface modules are signal splitter modules eachof which divides an RF signal received at its first interface connectorfrom said corresponding antenna into a plurality of divided RF signalseach having an equal signal strength which is a fraction of the signalstrength of said RF signal, said divided RF signals being provided tosaid second interface connectors, and wherein said respective controllerprovides control signals to said first switching means in each of saidfirst switching modules for interconnecting said first switchingconnectors with two of said second switching connectors such that one ofsaid receive terminals on said corresponding one of the radio channelunits is interconnected with the antenna having the strongest signalstrength of the received RF signals at the operating frequency of saidcorresponding one of the radio channel units and another of said receiveterminals on said corresponding one of the radio channel units isinterconnected with the antenna having the second strongest signalstrength of the received RF signals at the operating frequency of saidcorresponding one of the radio channel units.
 16. A modular interconnectmatrix for matrix connection of a plurality of antennas with a pluralityof radio channel units, wherein the antennas and the radio channel unitstransmit and receive RF signals at assigned operating frequencies,comprising:a plurality of switching modules, each having at least onefirst switching connector and a plurality of second switchingconnectors, each first switching module being connected by its firstswitching connector to a corresponding radio channel unit; firstswitching means in each one of said first switching modules forconnecting each one of said first switching connectors with any one ofsaid second switching connectors; a plurality of antenna interfacemodules, each having a first interface connector and a plurality ofsecond interface connectors, each antenna interface module beingconnected by its first interface connector to a corresponding antenna;wherein said second switching connectors are dimensioned forinterconnection with said second interface connectors; wherein saidsecond switching connectors and said second interface connectors arearranged on the respective first switching modules and antenna interfacemodules for interconnection of at least one of said second switchingconnectors on each of said first switching modules with at least one ofsaid second interface connectors on each of said antenna interfacemodules; wherein each radio channel unit is assigned to one group of aplurality of groups; a plurality of second switching modules each havinga first control connector and a plurality of second control connectors,said second control connectors being dimensioned for interconnectionwith said second interface connectors, and said second controlconnectors and said second interface connectors being arranged on therespective second switching modules and antenna interface modules forinterconnection of at least one of said second control connectors oneach of said second switching modules with at least one of said secondinterface connectors on each of said antenna interface modules, eachsecond switching module being assigned to a corresponding one of saidgroups; second switching means in each of said second switching modulesfor connecting each first control with any one of said controlconnectors; a plurality of frequency control means, each assigned to acorresponding one of said groups, for sequentially providing frequencycontrol signals each indicative of the operating frequencies of theradio channel units in said corresponding one of said groups; aplurality of scanning receiver means, each assigned to a correspondingone of said groups, connected to said first control connector of acorresponding one of said second switching modules, said scanningreceiver means being responsive to said frequency control signals and toRF signals provided by said antenna interface modules for providingsignal strength signals indicative of the signal strength of said RFsignal at the operating frequencies of the radio channel units in saidcorresponding one of said groups; and a plurality of controllers, eachassigned to a corresponding one of said groups, responsive to saidsignal strength signals for determining the antenna having the strongestsignal strength of the received RF signals at the operating frequency ofeach radio channel unit in said corresponding one of said groups, saidcontrollers providing control signals to said first switching means forinterconnecting each first switching connector with one of said secondswitching connectors such that each radio channel unit in saidcorresponding one of said group is connected with antenna indicated ashaving the strongest signal strength of the received RF signals at theoperating frequency of the radio channel unit.
 17. A modularinterconnect matrix according to claim 16 wherein each controllerprovides second control signals to said second switching means of acorresponding second switching module for interconnecting said firstcontrol connector to each one of said second control connectors of saidcorresponding second switching module in a predetermined sequence.
 18. Amodular interconnect matrix according to claim 17 wherein, between eachsecond control signal in said predetermined sequence, each controllercontrols a corresponding frequency control means to sequentially providesaid frequency control signals to said corresponding one of saidscanning receiver means, said frequency control signals corresponding tothe operating frequency of each radio channel unit in said correspondingone of said groups.
 19. A modular interconnect matrix according to claim18, wherein each of said first switching connectors on said firstswitching modules are connected to a receive terminal on saidcorresponding one of the radio channel units, and wherein said antennainterface modules are signal splitter modules each of which divides anRF signal received at its first interface connector from saidcorresponding antenna into a plurality of divided RF signals each havingan equal signal strength which is a fraction of the signal strength ofsaid RF signal, said divided RF signals being provided to said secondinterface connectors.
 20. A modular interconnect matrix according toclaim 18, wherein each of said first switching connectors on said firstswitching modules are connected to a transmit terminal on saidcorresponding one of the radio channel units, and wherein each antennainterface module includes a signal combiner module which combines RFsignals received at its second interface connectors from said transmitterminals into a combined RF signal which is provided to said firstinterface connector for transmission by said corresponding antenna andalso include a signal splitter module which divides an RF signalreceived at its first interface connector from said correspondingantenna into a plurality of divided RF signals each having an equalsignal strength which is a fraction of the signal strength of said RFsignal, said divided RF signals being provided to said second interfaceconnectors, said second interface connectors on said signal splittermodules being connected to said second control connectors.
 21. A modularinterconnect matrix according to claim 18 wherein the radio channelunits each comprise a diversity receiver having two receive terminalsfor receiving RF signals, wherein each of said first switching moduleshas two first switching connectors which are connected to acorresponding one of said receive terminals on said corresponding one ofthe radio channel units, wherein said antenna interface modules aresignal splitter modules each of which divides an RF signal received atits first interface connector from said corresponding antenna into aplurality of divided RF signals each having an equal signal strengthwhich is a fraction of the signal strength of said RF signal, saiddivided RF signals being provided to said second interface connectors,and wherein said controllers provide control signals to said firstswitching means in each of said first switching modules forinterconnecting said first switching connectors with two of said secondswitching connectors such that one of said receive terminals on saidcorresponding one of the radio channel units is interconnected with theantenna having the strongest signal strength of the received RF signalsat the operating frequency of said corresponding one of the radiochannel units and another of said receive terminals on saidcorresponding one of the radio channel units is interconnected with theantenna having the second strongest signal strength of the received RFsignals at the operating frequency of said corresponding one of theradio channel units.
 22. A modular interconnect matrix for matrixconnection of a plurality (N) of antennas with a plurality (M) of radiochannel units, wherein the antennas and the radio channel units transmitand receive RF signals at assigned operating frequencies, comprising:aplurality (M) of first switching modules, each having at least one firstswitching connector and a plurality (N) of second switching connectors,each first switching module being connected by its first switchingconnector to a corresponding radio channel unit; first switching meansin each one of said first switching modules for connecting each one ofsaid first switching connectors with any one of said second switchingconnectors; a plurality (M) of antenna interface modules, each having afirst interface connector and a plurality (X) of second interfaceconnectors, each antenna interface module being connected by its firstinterface connector to a corresponding antenna; wherein said secondswitching connectors are dimensioned for interconnection with saidsecond interface connectors; wherein said second switching connectorsand said second interface connectors are arranged on the respectivefirst switching modules and antenna interface modules forinterconnection of at least one of said second switching connectors oneach of said first switching modules with at least one of said secondinterface connectors on each of said antenna interface modules; eachradio channel unit being assigned to one group of a plurality (Y) ofgroups; a plurality of second switching modules each having a firstcontrol connector and a plurality (N) of second control connectors, saidsecond control connectors being dimensioned for interconnection withsaid second interface connectors, and said second control connectors andsaid second interface connectors being arranged on the respective secondswitching modules and antenna interface modules for interconnection ofat least one of said second control connectors on each of said secondswitching modules with at least one of said second interface connectorsof each of said antenna interface modules, each second switching modulebeing assigned to a corresponding one of said groups; second switchingmeans in each of said second switching modules for connecting each firstcontrol connector with any one of said second control connectors; and aplurality of switch control means, each assigned to a corresponding oneof said groups, for controlling said first and second switching means,each said switch control means including:frequency control means forsequentially providing frequency control signals each indicative of theoperating frequencies of the radio channel units in said correspondingone of said groups; scanning receiver means connected to said firstcontrol connector of a connector of a corresponding one of said secondswitching modules, said scanning receiver means being responsive to saidfrequency control signals and to RF signals provided by said antennainterface modules for providing signal strength signals indicative ofthe signal strength of said RF signals at the operating frequencies ofthe radio channel units in said corresponding one of said groups; and acontroller responsive to said signal strength signals for determiningthe antenna having the strongest signal strength of the received RFsignal at the operating frequency of each radio channel unit in saidcorresponding one of said groups, said controller providing controlsignals to said first switching means for interconnecting each firstswitching connector with one of said second switching connectors suchthat each radio channel unit in said corresponding one of said groups isconnected with the antenna indicated as having the strongest signalstrength of the received RF signals at the operating frequency of theradio channel unit.
 23. A modular interconnect matrix according to claim22 wherein each controller provides second control signals to saidsecond switching means of a corresponding second switching module forinterconnecting said first control connector to each one of said secondcontrol connectors of said corresponding second switching module in apredetermined sequence.
 24. A modular interconnect matrix according toclaim 23 wherein, between each second control signal in saidpredetermined sequence, each controller controls a correspondingfrequency control means to sequentially provide said frequency controlsignals to said corresponding one of said scanning receiver means, saidfrequency control signals corresponding to the operating frequency ofeach radio channel unit in said corresponding one of said groups.
 25. Amodular interconnect matrix according to claim 24, wherein each of saidfirst switching connectors on said first switching modules are connectedto a receive terminal on said corresponding one of the radio channelunits, and wherein said antenna interface modules are signal splittermodules each of which divides an RF signal received at its firstinterface connector from said corresponding antenna into a plurality ofdivided RF signals each having an equal signal strength which is afraction of the signal strength of said RF signal, said divided RFsignals being provided to said second interface connectors.
 26. Amodular interconnect matrix according to claim 24, wherein each of saidfirst switching connectors on said first switching modules are connectedto a transmit terminal on said corresponding one of the radio channelunits, and wherein each antenna interface module includes a signalcombiner module which combines RF signals received at its secondinterface connectors from said transmit terminals into a combined RFsignal which is provided to said first interface connector fortransmission by said corresponding antenna and also include a signalsplitter module which divides an RF signal received at its firstinterface connector from said corresponding antenna into a plurality ofdivided RF signals each having an equal signal strength which is afraction of the signal strength of said RF signal, said divided RFsignals being provided to said second interface connectors, said secondinterface connectors on said signal splitter modules being connected tosaid second control connectors.
 27. A modular interconnect matrixaccording to claim 24, wherein the radio channel units each comprise adiversity receiver having two receive terminals for receiving RFsignals, wherein each of said first switching modules has two firstswitching connectors which are connected to a corresponding one of saidreceive terminals on said corresponding one of the radio channel units,wherein said antenna interface modules are signal splitter modules eachof which divides an RF signal received at its first interface connectorfrom said corresponding antenna into a plurality of divided RF signalseach having an equal signal strength which is a fraction of the signalstrength of said RF signal, said divided RF signals being provided tosaid second interface connectors, and wherein said controllers providecontrol signals to said first switching means in each of said firstswitching modules for interconnecting said first switching connectorswith two of said second switching connectors such that one of saidreceive terminals on said corresponding one of the radio channel unitsis interconnected with the antenna having the strongest signal strengthof the received RF signals at the operating frequency of saidcorresponding one of the radio channel units and another of said receiveterminals on said corresponding one of the radio channel units isinterconnected with the antenna having the second strongest signalstrength of the received RF signals at the operating frequency of saidcorresponding one of the radio channel units.